Processing is one of the major challenges faced by the rubber industry in the preparation of blends and final products. Processing includes the mixing of ingredients, the preparation of homogeneous blends, and the incorporation of fillers and other rubber chemicals in an effective and efficient method, as well as the forming of profiles, assembly of these profiles and preparation of the final product by curing.
Processing aids are ingredients incorporated into the rubber compound to enhance processing of rubber compounds. Useful processing aids minimize or overcome one or more problems associated with the product fabrication, while maintaining or improving the product performance. Some known processing aids however, even when used in amounts beneficial to the processing of elastomers, such as halobutyl rubbers including bromobutyl and chlorobutyl, can deteriorate the aging and fatigue properties. The industry has a continuing need for processing aid improvements, particularly for halobutyl rubber; such processing aids desirably would improve the aging and fatigue properties and dimensional stability, or at least do not significantly deteriorate these properties when added to improve processing.
The tire industry is the major rubber industry that consumes large volumes of specialized halobutyl based compounds. One concern of the tire industry is the preparation of dimensionally stable profiles, and compounds with good mechanical properties and good fatigue properties. The tire industry uses processing aids to facilitate the compounding of the rubber formulations and preparation of dimensionally stable profiles. Another important requirement of the rubber compound is its aging resistance, e.g., the compounds are designed to have good fatigue resistance and cut growth resistance. Many conventional processing aids improve the processing, but may reduce the performance properties such as aging resistance.